In recent years, a type of mobile communications network known as an “ad-hoc” network has been developed. In this type of network, each mobile node is capable of operating as a base station or router for the other mobile nodes, thus eliminating the need for a fixed infrastructure of base stations. As can be appreciated by one skilled in the art, network nodes transmit and receive data packet communications in a multiplexed format, such as time-division multiple access (TDMA) format, code-division multiple access (CDMA) format, or frequency-division multiple access (FDMA) format.
More sophisticated ad-hoc networks are also being developed which, in addition to enabling mobile nodes to communicate with each other as in a conventional ad-hoc network, further enable the mobile nodes to access a fixed network and thus communicate with other mobile nodes, such as those on the public switched telephone network (PSTN), and on other networks such as the Internet. Details of these advanced types of ad-hoc networks are described in United States Patent Application Publication number US-2002-0058502-A1 entitled “Ad Hoc Peer-to-Peer Mobile Radio Access System Interfaced to the PSTN and Cellular Networks”, filed on Jun. 29, 2001, in U.S. Pat. No. 6,807,165 entitled “Time Division Protocol for an Ad-Hoc, Peer-to-Peer Radio Network Having Coordinating Channel Access to Shared Parallel Data Channels with Separate Reservation Channel”, granted Oct. 19, 2004, and in U.S. Pat. No. 6,873,839 entitled “Prioritized-Routing for an Ad-Hoc, Peer-to-Peer, Mobile Radio Access System”, granted Mar. 29, 2005, the entire content of each being incorporated herein by reference.
As can be appreciated by one skilled in the art, the connectivity between nodes in a wireless network, and the quality of the communication links between the nodes, can change due to the mobility of one or more nodes. For example, if nodes move out of each other's broadcast range, their direct link may fail. Also, if a node moves into an obstructed area, or into a high traffic or noisy area, the quality of the communication links between that node and other nodes can be adversely affected by this new environment and as a result the quality of the communication links can decrease. An example of a system and method for determining the mobility of a node in a network is described in U.S. Pat. No. 7,181,214 entitled “A System and Method for Determining the Measure of Mobility of a Subscriber Device in an Ad-Hoc Wireless Network with Fixed Wireless Routers and Wide Area Network (WAN) Access Point”, granted Feb. 20, 2007, the entire contents being incorporated herein by reference.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.